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Monday, February 28, 2011

There really has to be a better way to frame issues regarding threatened and endangered species and the economy. Otherwise, the economy will win every time. A story on NewsWest9, a West Texas media outlet is likely to get every uneducated, unemployed Texan pissed-off and the oil and gas lobby actively working with private landowners against the lizard. The Dune Sagebrush Lizard (Sceloporus arenicolus) is being considered for the endangered species list. The phrynosomatid lizard inhabits Shinnery Oak Dunes in West Texas and New Mexico and some of this habitat coincides with oil and gas hotspots. Really guys, this is so 1970's. Biodiversity needs to be seen as the valuable resource it is, one as valuable as oil and gas. And really, oil and gas needs to be seen as the energy source of the 19th and 20th centuries not the present century. The article quotes Morris Burns - as saying, "We're going to cut out some wells that would be drilled," oil and gas consultant, Morris Burns, said. "We're going to reduce the number of wells drilled in this formation. This is gonna cut out jobs." Morris, get with the program - you need some lessons in the importance biodiversity and a new job - consider being a consultant for wind and solar power, west Texas has plenty of both! Stop trying to scare people. You are doing society and the environment a great disservice. Be sure to watch the video that accompanies this article - talk about alarmist!

The VietnamnetBridge is reporting the story below. The turtle in question is the Vietnamese Pond Turtle, also known as the Annam Leaf Turtle, Annamemys (Mauremys) annamensis (Siebenrock, 1903) (family Geoemydidae) the species is known only from one extant population in near Hội An in Quảng Nam Province which was discovered in 2006. Prior to this rediscover no one had seen it in the wild since 1941, but it did occasionally turn up in markets and in the animal trade and it is being bred in captivity (see references below).

Rare turtle hunted to brink of extinction

Hunting the highly endangered Annam pond turtle has become popular in the central province of Binh Dinh after the price of a kilogramme of its meat skyrocketed from a few hundred thousand dong to upward of US$1,000.

Seeing the huge profits that the reptile – known as rua dong in Vietnamese – is fetching, many people in Phu My, Phu Cat, An Nhon, and Hoai Nhon districts have taken to it.

Tu and his wife, farmers in Phu Cat, went turtle hunting and did not have time to care for their 2,000-square metre cucumber field. As a result, the entire crop died, but after two months of hunting, the couple have yet to trap a single animal.

Dao, a turtle trader in Phu Cat, said she sold the animals she buys to an agent in the north who had been willing to buy even small rua dong weighing less than 200 grammes.Local traders said the agents in the north in turn sold the turtles to China for medicinal and other purposes.

Rua dong, also called rua Trung bo, is an endemic species found only in some central Vietnamese provinces.

It has been listed in the International Union for Conservation of Nature's Red List of Threatened Species since 2005.

Nguyen Huu Hao, deputy director of the province's Department of Agriculture and Rural Development, said few animals were caught.

Asked why the reptile had not been protected, he said: "It is hard to ensure effective prevention because people mostly go to catch [it] at night and do so stealthily."

Nguyen Hieu Hoa, head of the province's Forest Protection Sub-department, however, claimed: "We are taking measures to prevent [it] and protect the endangered turtle."

Reticulated Pythons (Broghammerus reticulatus) inhabit South and Southeast Asia and they are the longest snake alive today. Humans are attacked and eaten by these super predators and in Indonesia and Sarawak (Malaysia) there are 20 reasonably reliable cases known in the last 150 years. Ruud de Lang reports that this is an underestimate of reality because many cases of Reticulated Python predation on humans remain known only at the local level. He investigated several incidents. As is often the case, food webs are more complex that first thought, and humans do prey upon and eat Reticulated Pythons. He notes the difficult in deciding why the Reticulated Pythons attacked humans. They may have been accidental encounters that resulted in a defensive attack or a hungry snake waiting in ambush for a prey. Large Reticulated Pythons are strong and a single person is no match for a snake that is 3 m long or more.

Saturday, February 26, 2011

The following is based upon Rodda et al. 2011. It is taken from their introduction and has been slightly edited for readability.It should be pointed out that Python molurus and Python bivittatus are now regarded as distinct species.

In 2008 the U.S. Fish and Wildlife Service (USFWS) solicited advice from the general public on the potential merits of restricting the importation of nine exotic species of giant constricting snakes. The intent was to reduce the risk of introducing the invasive species into the USA. The species list included the Indian Python (Python molurus) and what at the time was considered to be its subspecies. The best known of which is the Burmese Python, Python molurus bivittatus. At about the same time, Rodda et al. published results of an analysis of the areas of the U.S. that are climatically matched to the native range of the Indian Python. The publication of the map and the USFWS Notice of Inquiry were connected in the sense that USFWS had joined the U.S. National Park Service in funding the U.S. Geological Survey (USGS) study. Some sections of the public perceived the work as interagency collaboration in support of regulation of trade in giant constrictors, despite the fact that USGS had no policy position on invasive species regulation, and was under no pressure, either imposed by the funding sources or self-imposed, to support regulation, or bias the size or extent of the U.S. area that climatically matched the python’s native range. The climate match study was to inform the discussion. Pyron et al. (2008) countered with an alternate map showing areas of the U.S. that climatically matched the python’s native range; their map was embraced by opponents of regulation because it showed a much smaller area of climatic agreement – the area that could be inhabited by the pythons. And, Pyron et al. concluded that ‘‘The Burmese python is strongly limited to the small area of suitable environmental conditions in the United States it currently inhabits…’’ They also averred, ‘‘The proposed expansion of the python into the continental United States would require an expansion of the actual tropical marshland habitat comprising most of the Everglades, not simply the presence of similar temperature and precipitation conditions.’’ If either of these claims were true, no further areas of the U.S. would be at risk of colonization, and regulation of U.S. trade in this species would be largely moot. Although Pyron et al. did not expressly tie their climate match to policy, they did lay claim to the policy high ground by asserting that, ‘‘The alarmist claims made by USGS could potentially hamper scientific discourse and inquiry into the problem, especially with regard to policy-making.’’ The notice of inquiry and subsequent proposed rulemaking generated a substantial public response, with a large number of comments received (55,600), and most of the criticism focused on the climate matching result for one of the nine species under consideration, the Indian Python. The intensity of the public’s reaction can be used to document climate matching can be a key element in establishing environmental policy. Also, differences among approaches to climate modeling are critical for evaluating the scientific basis for the policy. One element of this controversy is the herpetological facts that were the basis for the models. In these, Rodda et al. and Pyron et al. did not noticeably differ and the herpetological facts will not be discussed further. Another element of the controversy is the modeling approach, for which the two teams took divergent approaches: Rodda et al. adopted a climate suitability algorithm based on first principles, and Pyron et al. used a statistical tool to discover a climate suitability algorithm. Ideally, one would have some method for validating the projections, but there is no obvious way to validate the likelihood of a hypothetical event. Furthermore, the validity of these specific models might rest on factors unique to the Indian Python, and therefore be of limited interest.

Species distribution models are often used to characterize a species’ native range climate, so as to identify sites elsewhere in the world that may be climatically similar and therefore at risk of invasion by the species. Rodda et al. have evaluated a number of species to assess MaxEnt’s (Maximum Entropy model) utility for vertebrate climate matching.

They found MaxEnt models to be very sensitive to modeling choices and selection of input localities and background regions. As used, MaxEnt invoked minimal protections against data dredging, multicollinearity of explanatory axes, and overfitting. As used, MaxEnt endeavored to identify a single ideal climate, whereas different climatic considerations may determine range boundaries in different parts of the native range. MaxEnt was extremely sensitive to both the choice of background locations for the python, and to selection of presence points: inclusion of just four erroneous localities was responsible for Pyron et al.’s conclusion that no additional portions of the U.S. mainland were at risk of python invasion. When used with default settings, MaxEnt overfit the realized climate space, identifying models with about 60 parameters, about five times the number of parameters justifiable when optimized on the basis of Akaike’s Information Criterion.

Rodda et al. (2011) concluded that when used with default settings, MaxEnt may not be an appropriate vehicle for identifying all sites at risk of colonization. Model instability and dearth of protections against overfitting, multi-collinearity, and data dredging may combine with a failure to distinguish fundamental from realized climate envelopes to produce models of limited utility. A priori identification of biologically realistic model structure, combined with computational protections against these statistical problems, may produce more robust models of invasion risk. The entire article can be found by the linked reference below.

Friday, February 25, 2011

In a letter to Your Abiline On-line, regarding rattlesnake roundups, Jeremy Wilson, describes the even as, "One of the largest gatherings of ignorant, inhumane hillbillies in the country." And, notes that the events are about money and a tradition that teaches a disrespect toward nature. There are about 20 comments on his letter, many of which are worth reading and show a lot of informed and uninformed opinions. Total public humiliation of the people and organizations who support these events may be required to end them. Mr. Wilson had made an attempt. The leter and comments can be found at Your Abiline On-line. See the previous post that dealt with the article under discussion.

Thursday, February 24, 2011

Howdy Herpers,
It is a rare to actually record snake mortality--especially if it isn't a transmittered snake. Such an opportunity presented itself from February 9 to February 13 of this year.

On Wednesday February 9, Dale DeNardo was visiting our hill to document some of our Gila Monster activity. He did so with our full blessing and support. While doing his rounds, he discovered a sweet young female atrox basking, with head and neck partially out of a soil hole. He snapped a quick photo, flagged the site, and moved on.

On Sunday, 13 Feb, Dale led Brian Park, Karla Moeller and fat, dumb and happy here to the spot. The snake was still out, but not looking so good. We'll let the images tell the rest of the story.

Pic 1: Photo of snake insitu as found, 9 Feb. Photo by Dale DeNardo.

Pic 2: Photo of snake is situ on 13 Feb.Pic 3: Dale gently grabbed the snake behind the neck. The jaws opened slowly, as if it was a last gasp. I don't think the snake was alive at this point, but there was certainly some reflex action. No stench, no ants, as fresh dead as one can ever expect to see without actually killing it oneself.

The short story is this: the poor thing overestimated her ability to crawl out of a tight soil hole. We pulled and tugged on her until I thought I'd break her in half. We tried digging her out with knives and sticks, but there was no release. We buried her, and I will return with a shovel next weekend to excavate, check for PIT tag, etc.

A full up report will happen next week. For now, that's all that is fit to spit.
Best, roger

In a forth coming article Freek Vonk and colleagues (2011) note that snake venoms are a grossly under explored resource in pharmacological prospecting and that recent discoveries in snake systematics demonstrate that former taxonomic bias in research has led to the neglect of thousands of species of potential medical use. Recent discoveries suggest an unexpected degree of variation in venom composition among snakes, variation that differs not only from species to species, but during the life of an individual. The molecular mechanisms underlying this diversity are only beginning to be understood. However, Vonk and colleagues note the enormous potential of snake venom as resource for pharmacological prospecting give new the methods of finding potentially useful molecules. This discovery comes at a time when snake populations are threatened with extinction from human degradation of the environment. Many venom proteins affect the hemostatic system and have been used as defibrinogenating agents for several clinical conditions including deep vein thrombosis, myocardial infarction, and pulmonary embolus. Drugs already derived from snake venoms include Ancrod (Arvin) from the venom of the Malayan Pitviper (Calloselasma rhodostoma), batroxobin (Reptilase) from the lancehead (Bothrops atrox), and crotalase from the Eastern Diamondback Rattlesnake (Crotalus adamanteus). Aggrastat (tirobifan) was developed from the venom of the Saw-scaled Viper (Echis carinatus), and is used as an antiplatelet drug for unstable angina. Venoms with procoagulant properties are useful for the diagnosis of clotting abnormalities. ‘‘Ecarin’’ (E. carinatus) and ‘‘taipan time’’ (Oxyuranus scutellatus) are used for assays for phrothrombin, and Russell’s viper (Daboia russelii) venom assays for factor X and for monitoring anticoagulant therapy. Angiotensin-converting enzyme (ACE) inhibitors were developed from an enzyme isolated from the venom of the Brazilian Pitviper (Bothrops jararaca) to treat high-blood pressure and heart disease. Many venoms have analgesic properties, Hannalgesin is derived from the venom of the King Cobra (Ophiophagus hannah) is now in clinical trials. Promising molecules for pain relief have been isolated from the Tropical Rattlesnake (Crotalus durissus terrificus) as well as related species. The anticancer properties of venoms are also being explored. Malignant brain and spinal-cord tumors (gliomas) are not curable by surgery because they invade the surrounding brain tissue without clear boundaries, making removal impossible. Disintegrins, like contortrostatin from American Copperhead (Agkistrodon contortrix) venom, prevent cells from sticking together, and inhibit their interaction with surrounding tissue, resulting in a blockage of cell motility and invasiveness. Most of the exploration of snake venoms to date have focused on vipers and elapids, but there are many other families of snakes that produce valuable venom molecules - and this resource is only starting to be recognized. In order to keep these valuable molecules available for humans it is necessary to conserve snakes.

Wednesday, February 23, 2011

Dr Snake' Bears Fangs for Conservation
Former doctor Chen Yuanhui has gone from saving people from snakes to saving snakes from people.

Chen Yuanhui - aka 'Dr Snake' - poses in this 2010 file photo with a wild venomous Mangshan pit viper, an endangered species he discovered in 1989 and one he has worked to protect ever since. [China Daily] Add caption

Since the 62-year-old discovered a new species of venomous serpent when treating an elderly patient who sustained a bite in 1984, he has devoted his life to the creatures' preservation.

He has become known as "Dr Snake" in his community in mountainous Mangshan, in Central China's Hunan province, the place from which his Mangshan pit viper takes its appellation.

A statue of him with one of the serpents slithering over his shoulders stands at the gate of the Mangshan Museum of Natural History, where Chen works as the curator. The monument was donated by local businesspeople in 2008 as a tribute to his work.

"I hadn't heard of the snake until 1984," Chen said.

That was the year he was working at the staff hospital of the Mangshan Forestry Administrative Bureau when an elderly snakebite patient described an ophidian variety unlike anything Chen had seen.

The patient said the creature had green-and-yellow markings and a white tail.

It reminded Chen of the local Yao ethnic group's venerated totem - the "small, green dragon" - and he set out to hunt for the species.

In October 1989, he heard some people had captured a nest of 23 snakes. He went to investigate and discovered the creatures fit the description given by the old man years before.

He took the specimens to herpetologist Zhao Ermi, and, by 1990, the species was confirmed to have been previously undiscovered and endemic to the country.

Chen began researching the creatures and kept seven specimens in his home.

He spoke of them as if they were his children.

"The snakes are very lazy," he said. "Most of the time they just lay in the cage and don't move until later in the afternoon. When they're hungry, they tap against the walls to make noise."

The sounds of the creatures and odor of their feces upset his wife and daughter for years and caused family disputes. Still, his family members were his biggest supporters, he said.

"My wife used to call me a 'cold-blooded animal, just like the snakes'," he recalled, tearing up at the thought of the woman, who passed away in 2006.

Chen has survived nine bites over the past three decades. The last one, which he captured on film, nearly cost him his life - and did cost him a finger - in 2003.

There are between 300 and 500 Mangshan pit vipers in the wild, and the species was included on the International Union for Conservation of Nature's Red List of Threatened Species in 1996. Their numbers are fewer than the giant pandas', earning it the nickname "the panda of snakes".

However, the reptile - regarded by many in herpetological circles as "the most beautiful of snakes" - is not included on the List of National Key Protected Wild Animals in China.

Consequently, there are no severe punishments for hunting the wild creatures.

Chen said he has rejected countless offers from hopeful buyers.

"If I started selling snakes, the villagers would follow my lead and catch snakes on the mountains," he said.

"Many villagers have the snake smugglers' contact numbers the money is much more than what they could earn growing crops in a year," Chen said.

About 80 forest rangers keep poachers away from the MangshanNational Nature Reserve. But smugglers still enter the snakes' habitat through the other side of Hunan's border with northern Guangdong province, Chen said.

The buyers are not just reptile lovers but also research institutions and zoos, Chen said.

Smuggling of the snakes to such overseas destinations as the United States and Germany has also become rampant, Chen added.

The Mangshan Forestry Administrative Bureau founded, and made Chen chief of a Mangshan pit viper institute in 2008.

"I've never been a full-time researcher," Chen said, joking that his study of the pit viper is more like a hobby.

But raising public awareness about the importance of protecting snakes has become more like a mission, one he sustains through his blog.

"After all,I am the only researcher of the Mangshan pit viper in its natural habitat," Chen said.

He plans to open a small outdoor area in the forest for research and for tourists to see the creatures in their natural habitat.

"Glass rooms are not good for the snakes. They should live in the wild," he said.

He recalled that a burglar broke the door of an observation station in the museum and stole one of the pit vipers in 2005.

"When the snakes can hide between stones, they'll be more difficult for thieves to catch," he said.

Tuesday, February 22, 2011

Fire maintained ecosystems are often found in geographic regions with Mediterranean climates - southern California, southwest Australia, and of course the Mediterranean. Burning vegetation is an inconvenience, and even prescribed burns are often objected to by local citizens. But, burning-off left-over agricultural biomass has increased in many places. Suppressing fires can lead to the build-up of fuel -dead, dry vegetation- in fire maintained ecosystems and result in increased hazards to both humans and wildlife. How wildlife populations deal with fire is of interest for understanding adaptations to fire and for conservation. Ana Sanz-Aguilar and colleagues have examined how the Iberian Spur-thighed Tortoise, Testudo gracea ibera, manges to coexist with fire at the Cumbres de la Galera Biological Reserve in the Sierra de la Carrasquilla, in Spain. Their study area supported a high density population (about 20 tortoises per hectare) of Spur-thighed Tortoise and they estimated tortoise populations in areas that had frequent fires and areas that had not been burned. The Spur-thighed Tortoise is a long-lived species of the Mediterranean shrublands and the tortoises spend much of their lives sheltered under the vegetation or underground in burrows. These tortoises also bury themselves for hibernate and aestivate, so that they are protected from extreme temperatures, predators and possibly from fires. They found fire caused direct and delayed reductions in local survival, with young individuals being the most affected. Fire-related mortality was highest in juveniles and subadults than adults; this seemed to be related to differences in burrowing behavior. Summer fires had a lesser impact on adults because they spend summer and winter underground in burrows or by burying themselves to avoid temperature extremes. Juveniles and subadults tend to use more superficial burrows or take cover under the vegetation only a few centimeters in depth, thus and are exposed to higher temperature and smoke. The study areas that had fire frequencies similar to those occurring in areas uncontrolled for burns (less than one fire every 20–30 years) tortoise populations were able buffer the effects of fires. But, when fire frequency increased the probability of extinction dramatically increased, except for the largest populations. Thus, T. graeca is able to cope with natural fire frequencies, but the effects of more recurrent fires may severely threaten the species.

Monday, February 21, 2011

The following article is from Your Abilene Online, follow the link to the original article. A little education and an attitude adjustment is needed here.

BIG COUNTRY JOURNAL: Snakes on the Plains
Annual roundup of rattlers just around corner
By Ron Erdrich erdrichr@reporternews.com
Posted February 20, 2011 at 10:30 p.m.

Brittany Lashinski wishes she could do it all again. But for Miss Snake Charmer 2010, it's time to pass-on the crown.

If March is around the corner, so is the World's Largest Rattlesnake Roundup in Sweetwater and its companion event, the Miss Snake Charmer Pageant.

Lashinski, 17, said the past year has been unique for her.

"I got to meet a lot of people, and I took a lot of interviews," she said, adding that, though her time in the role is ending, she was just asked to do a commercial.

She learned a lot about herself, too. It takes courage to get up on stage, speak eloquently, model a gown and perform before a large crowd, she said. The experience forged a new self confidence.

"I learned I can talk in front of people and that I can be that girl, to wear the crown," she said. "Even though I'm not wearing heels every day, you can do whatever you set your mind to."

On Friday, 20 girls presented themselves to the Big Country as the roundup held its annual Media Day. The pageant awards scholarship money to the winners. All contestants must be of high-school age and live within 75 miles of Sweetwater. The roundup weekend begins March 10 with a parade and the pageant that evening. March 11 is when the doors open at the Nolan County Coliseum for the roundup.

The Sweetwater Jaycees runs the roundup, and spokesman Riley Sawyers said its purpose is to keep the rattlesnake population under control. Now in its 52nd year, he also said the annual event educates people on what to do if they encounter rattlesnakes.

"We're not out to deplete the snake population; this area can hold a 50-year average of over 5,000 pounds of snakes per year," he said. "If we didn't have the roundup, there's no telling how many snakes would be in your front yard, your backyard, around your kids and your animals."

With the recent warm weather, he thinks if it continues to stay warm that the turnout of snakes and visitors could be very high.

"I'm a snake hunter myself, and this year I can definitely say, just from my own experience, it's better than last year," he said. "I've been out several times this year, and I'm already past the amount of snakes I caught last year, and I haven't even reached the peak of my hunting yet."

Hunters are paid for the snakes they bring in. The animals are weighed, measured, milked for venom, and then killed and skinned. Their meat is harvested and used for the roundup's signature dish, deep-fried snake meat.

One of the duties of Miss Snake Charmer is skinning snakes, and this year's contestants got their first opportunity to do so Friday. Lashinski said last year she was squeamish about it, but this time around she stepped up and showed them how it was done.

"I was a big baby last year, I cried because I didn't want to do it," she said, changing her mind at the time and having a good time with it. "It's kind of gross, but you get used to it, you see the fun in it."

The Search for Lost Frogs, began in August 2010 and was the initivate of Conservation International (CI) and the IUCN Amphibian Specialist Group (ASG), with support from Global Wildlife Conservation (GWC)> The effortattempted to document the survival status and whereabouts of threatened amphibian species not seen in over a decade.It involved 126 biologists in 21 countries. Here is a recent report on the efforts from Conservation International.

After five months of expeditions in 21 countries, researchers participating in CI’s Search for Lost Frogs have rediscovered 15 amphibian species not seen in more than a decade — and found three additional species that may be new to science. Here, CI’s amphibian conservation officer Robin Moore recounts his experience unearthing a species lost for 30 years.

Lost things usually turn up in the last place you expect to find them. Car keys behind the fridge. Glasses in a flowerpot. But the last thing I expected to find in a rubbish bin in India’s Western Ghats was something last seen the year “The Empire Strikes Back” hit the big screen. Yet, as I slowly lifted the lid covering a small plastic bin in the kitchen of our retreat, I am not sure who was more surprised: me or the frog that started bouncing from wall to wall like a pinball.

And so it was that the Silent Valley tropical frog (Micrixalus thampii) was rediscovered after 30 years. It was an auspicious start to the “Lost! Amphibians of India” campaign, inspired by our global Search for Lost Frogs and launched just two days earlier at the University of Delhi.

There is something rewarding about finding something you thought was lost. I always appreciate house keys a little more after they have been missing. And so it is with amphibians; finding species that we thought were gone provides a rare good news story and reveals a second chance at survival.

Why is this important? Because amphibians are at the forefront of a “sixth great extinction” — the largest since the dinosaurs disappeared from our planet. We have a crucial opportunity to understand why some species survive while those around them are vanishing. Knowledge of what makes a species resilient to the driving forces of extinction could help us stem the crisis and maintain our lifeline to a healthy future.

But as teams of scientists set out on an unprecedented collaborative global effort to search for “lost” species in August last year, I really didn’t know what to expect. I would be lying if I said I didn’t worry that all teams would come back empty-handed.

Then the field reports started pouring in, so evocative and dripping with enthusiasm that I felt like I was right there with the researchers, wading up streams and turning over logs. I was transported from the high Andes of Chile to the dense jungles of Cameroon and Malaysia. I quickly became immersed in the thrill of the chase; the element of exploration ignited my childlike sense of curiosity. The passion of all the teams was contagious and inspiring.

And then there were moments of unadulterated joy. On Saturday, September 4th, I opened my inbox to find an email from N’Goran Koume, sent from a cybercafé in Danané, Ivory Coast: “Dear Robin, Yes, it is fantastic. The Mount Nimba reed frog [Hyperolius nimbae] has been found after 43 years!” I almost fell out of my chair. The excitement in the email was palpable. The hairs on the back of my neck stood on end.

Although the successes were few and far between, each was like a generous shot of tequila (the good stuff).

Eventually I was lucky enough to accompany teams of local and international herpetologists into the field to join the search. I clambered around steep hillsides in Colombia, drove through rivers to reach craggy peaks in Haiti, and came face-to-face with elephants in India. Long hours of fruitlessly searching for creatures that have evolved over hundreds of millions of years only strengthened my respect and admiration for the people that are dedicating their lives to understanding our planet and its fascinating inhabitants. I was bowled over by the dedication of local scientists, and reminded that we should never underestimate the knowledge of local communities, who frequently steered search teams in the right direction.

Now that the Search for Lost Frogs has come to a close, it is time to reflect on what it means for amphibians — and for us. We are working with local partners in Ecuador toward the protection and monitoring of the Rio Pescado stubfoot toad (Atelopus balios), which clings onto survival in one stream. Through the “Lost! Amphibians of India” campaign, we have forged partnerships and created a platform to catalyze conservation efforts in the forests of the Western Ghats, one of the richest and most threatened habitats on earth.

But what about the species that were not found? More than nine out of ten of the species searched for did not turn up, a sobering indication that many of these species may indeed be gone forever. They are sounding an alarm that the ecosystems upon which they, and we, depend for survival are sick. It is up to us to do something about it. Whether it is helping to protect the last home of the Rio Pescado stubfoot toad, or spreading the word about the amphibian extinction crisis and why we should care, please join me in protecting these jewels.

While time is of the essence, with each rediscovery comes a reassurance that it is not too late. Let’s not wait until it is.

Recently this blog reported on a forthcoming article by P. Chippaux that suggests snake bite mortality in sub-Sahara Africa is much lower than previously thought - about 7000 deaths per annum. Now, a new study by Sebastien Larreche and colleagues examined 12-years of viper bite data from the Republic of Djibouti, and compared the impact of an early administration of antivenin versus a delayed administration on restoring the victims’ normal blood chemistry. The study looked at 73 cases (from 1994-2006), where patients presented with symptoms of viper bites in the intensive care unit of the French military Hospital, in Djibouti. Snakes involved in the bites were Echis pyramidum and Bitis arietans, and patients treated prior to 2001 received Echis-Bitis-Naja serum (Pasteur-Mérieux, Lyon, France), those treated after 2001 received FAV-Africa (Aventis-Pasteur), which is useful against Echis, Bitis, Naja, and Dendroaspis venoms. The research team examined antivenin efficiency in correcting blood chemistry to the time of treatment - before or after the 24th hour after the bite. Forty-two patients (58%) presented with bleeding - blood in their urine, coughing blood, or bleeding gums. Larreche and colleagues found antivenin was effective in improving hemostasis, and the time to normalization of blood chemistry was similar, whether the treatment was started before or after the 24th hour after the bite. They authors report that antivenin should ideally be administered as early as possible. In Africa, time to treatment often exceeds 24 hours because of the distances and transportation available. However, the results suggest that antivenom should be used despite the delay in getting treatment, and that the fact that time has elapsed between the envenomation and treatment should in no way prevent the use of antivenin immunotherapy for treatment of African viper bites.CitationLarréché, S., G. Mion, A. Mayet, C. Verret, M. Puidupin, A. Benois, F. Petitjeans, N. Libert, and M. Goyffon. 2011. Antivenin remains effective against African Viperidae bites despite a delayed treatment. The American Journal of Emergency Medicine, 29(2):155-161.

Sunday, February 20, 2011

The genus Cryptelytrops contains 13 species of Southeast Asian green pit vipers, Malhotra et al (2011) have now described two more that are similar to Cryptelytrops macrops and have been confused with it. The three species can be distinguished by genetic means, multivariate analysis of morphology and some aspects of coloration. The authors describe Cryptelytrops cardamomensis from southeastern Thailand and the Cardamom Mountains of southwestern Cambodia and Cryptelytrops rubeus from southern Vietnam and eastern Cambodia. The Large-eyed Pit Viper, C. macrops, is restricted to Thailand, southern and central Laos, and northeastern Cambodia. All three species are present in Cambodia, but have disjunct ranges that corresponding to three separate highland regions in southwestern (Cardamom Mountains), northeastern (western edge of the Kontum Plateau) and eastern (low elevation hills on the western edge of the Langbian Plateau) Cambodia for C. cardamomensis, C. macrops and C. rubeus respectively. However, there is still considerable morphological variation between geographically separated populations of C. macrops and greater sampling in southern and northern Thailand in particular may be required before the species diversity of this group is fully clarified. All of these snakes are often found in vegetation that is near streams.

Saturday, February 19, 2011

In 2008 Ernst et al. described the Giant Squeaker Frog, Arthroleptis krokosua from West Africa's Krokosua Hills Forest Reserve (KHFR), in south-western Ghana. It is the largest member of the genus from West Africa and differs from other West African Arthroleptis by its large size, its peculiar coloration and some morphology. It is most similar to large members of the genus from East and Central Africa, particularly A. variabilis and A. adolfifriederici from which it differs in coloration, larger size (> 43 mm), and head shape. Genetic divergence was about 5 % between Arthroleptis krokosua and A. variabilis, and A. krokousa seems to have no apparent affiliations to any other West African Arthroleptis that are smaller in size and have a distinctly different body shape. Adum et al (2011) surveyed three commercially logged forest reserves that included the type locality of A. krokosua (KHFR). The study sites have a climate characterized by a wet season with two rainfall peaks falling between May–June and September–October, and annual rainfall of 1200–1800 mm. The dry season is between November and March. They found more specimens of the Giant Squeaker, that were juveniles and subadults during the middle of the rainy season at the type locality and at Sui River Forest Reserve. Despite the new localities for the species the authors consider it to be threatened. Surveys of Ghana forests in recent years have not detected the species. The two forests where A. krokosua occurs are approximately 30 km apart and even though the areas are considered reserves they are under severe threats from logging , fragmentation, farming and mining. Logging and farming might be the reason why over half of the KHFR amphibian fauna already consists of non-forest specialists. The authors further suggest data on the breeding habitats and population estimates are needed to plan for long-term conservation of this peculiar Ghanaian forest frog.

Thursday, February 17, 2011

The following press release reports on research done using the Western Clawed Frog, Xenopus tropicalis. It has been long suspected that pharmacetual products in the water impact organisms, this research supports that view.

Sterility in frogs caused by environmental pharmaceutical progestogens
Press release published 2011-02-16
Frogs appear to be very sensitive to progestogens, a kind of pharmaceutical that is released into the environment. Female tadpoles that swim in water containing a specific progestogen, levonorgestrel, are subject to abnormal ovarian and oviduct development, resulting in adult sterility. This is shown by a new study conducted at Uppsala University and published today in the scientific journal Aquatic Toxicology.
Many of the medicines that people consume are released into the environment via sewage systems. Progestogens are hormone preparations used in contraceptives, cancer treatment and hormone replacement therapy for menopausal discomfort. Different kinds of progestogens have been identified in waterways in a number of countries. Associate professor Cecilia Berg and doctoral student Moa Kvarnryd at the Department of Environmental Toxicology at Uppsala University have shown that levonorgestrel can cause sterility in female frogs at concentrations not much higher than those measured in the environment. The research group is part of MistraPharma, one of the world's largest research networks focusing on pharmaceuticals and the environment.

Female tadpoles that swam in water containing low concentrations of levonorgestrel exhibited a greater proportion of immature ovarian egg cells and lacked oviducts, entailing sterility. The African clawed frog (Xenopus tropicalis) served as the model organism. It is during the tadpole stage that development of frog reproductive organs begins. The process is governed by the hormone system. The findings underscore the importance of studying how pharmaceuticals affect animals in our environment, which is one objective of MistraPharma.

“Our findings show that pharmaceuticals other than oestrogen can cause permanent damage to aquatic animals exposed during early life stages,” says Cecilia Berg.

The herpetofauna of Morocco is characterized by high endemism (27.6%) and species richness (at least 98 species) and is the center of diversity for some reptile genera, such as Acanthodactylus, Chalcides and Blanus. The IUCN Global Category and Criteria suggest 9.7% of Moroccan species are threatened (9.7%) and the percentage increases to 12.4% when applying Regional Category and Criteria. The Kingdom possesses the richest and most varied herpetofauna in the Maghreb and the western Mediterranean. In addition to the endemics a number of European relict species also inhabits the country. Most studies of the fauna have not been concerned with conservation. Philip de Pous and colleagues have now identified those areas with the highest species richness; proposed future important biological and ecological sites and identified priority areas. They found species richness highest in four disjunct areas: the northernmost Tingitana peninsula; the eastern Mediterranean coastline; the Atlantic coastal area; and the Middle Atlas region. And, they identified regions with moderate to locally high richness along the Middle Atlas and High Atlas Mountains and the Sahara desert. Areas with low species richness include the semi-desert plain of Marrakech and the semi-deserts east of the High Atlas. The Anti-Atlas Mountains were also identified as having low species richness.

Wednesday, February 16, 2011

The oceans of the Mesozoic contained
species that we know today only from their fossil remains, species which looked
quite unlike anything we are familiar with today. Ichthyosaurs may have looked
slightly familiar, because despite the fact they were reptiles, they had
dolphin- or fish-shaped bodies. The “fish lizards” first appear in the fossil
record about 225 million years ago (MYA) and disappear about 90 MYA. While most
species were in the 2 to 4 meter range, some grew larger, and a few of the
earliest forms were less than 2 m long. Some specimens have been exceptionally
well preserved and provide information on soft tissue, diet and reproduction. Their
relationship to other tetrapods has been controversial and there has been much
speculation on their origin but a consensus has been building that ichthyosaurs
are indeed diapsid reptiles. The absence of a lower temporal region has been
one of the sticking points to accepting them as diapsids. Liu et al. (2011)
have now described the cranial skeleton of a new mixosaurid ichthyosaur specimen with a well-preserved lower temporal region from the Anisian Guanling
Formation of easternYunnan. It is has the most primitive lower temporal region known
in ichthyosaurs, and it was well preserved. The specimen provides definite
direct evidence for the diapsid origin of ichthyosaurs. It also gives strong
support to the hypothesis that the lower temporal fenestra in ichthyosaurs is
lost due to the reduction of the jugal and the quadratojugal that comprise the
primitive lower temporal arcade in diapsids. Given that these marine reptiles
are in fact diapsids, the question remains what clade did they arise from? They
may have shared an ancestor with the lizards.

Tuesday, February 15, 2011

The Timber Rattlesnake, Crotalus horridus, is a long lived (20 to 30 years) forest-floor predator that plays an important role in ecosystem energy flow. As such, Timber Rattlesnakes contribute substantially to the stability of the structure and function of forest communities. However, over much of its distribution the timber rattlesnake is exposed to direct persecution and extensive habitat loss causing many populations to disappear. Currently Timbers are listed as threatened, endangered, extirpated, or a species of concern in most of the states it inhabits and the continued existence of viable populations is dependent on large forest tracts throughout Appalachia. The Timber Rattlesnake maintains sizable populations that are associated with large areas of publicly owned forest land which are multiple-use management areas. Thus the rattlesnake is sharing land that is used by humans for recreation, wildlife, and timber production. This association provides an opportunity for successful Timber Rattlesnake conservation but information on the direct or indirect effects of logging on this species has not been examined. Howard K. Reinert and colleagues have studied the direct impact of current logging practices and habitat alteration on a population of timber rattlesnakes in Pennsylvania before, during, and after commercial timbering operations; and examined the short-term response of snakes to logging activities. The research team monitored 67 snakes with radio telemetry over periods as long as four years, and marked and recaptured 306 snakes. Survey efforts were done before, during, and after commercial logging operations on three parcels of land. Snake mortality related to logging was low, less than 2% of the population per year, but potential mortality could have reached 7%. Logging and the subsequent habitat changes did not alter behavior or movement patterns of monitored snakes and the snakes with established activity ranges used these areas both during and after logging operations.Logging increased structural diversity of the habitat and, concurrently, diversity of habitat used by timber rattlesnakes increased. The results suggest that the opportunity exists to develop forest management practices that provide timber products while limiting the impacts timber rattlesnake populations. The authors suggest logging contractors be required to avoid killing snakes while they are working. The entire article can be found on-line.

The Wild Equity Institute (WEI), a San Francisco-based environmental policy advocacy organization, sent a letter to the mayor of San Francisco and board of supervisors calling for the conversion of Sharp Park Golf Course to a nature reserve for endangered native frog and snake species and a park. The suggestion is contrary to those proposed in a 2009 study done by SFRP. The newest study, prepared by ESA PWA, an environmental consulting firm, makes four assertions:

1) “The least costly restoration alternative that would most benefit endangered species at Sharp Park would remove the golf course and restore the natural ecosystem, saving taxpayers tens of millions of dollars in a time of budget crisis.”

2) “Restoring the natural processes of Laguna Salada will preserve the Sharp Park beach, while the Park Department’s proposal will result in the beach eroding away.”

3) “Sharp Park historically provided more extensive habitat for the California red-legged frog and the San Francisco garter snake, and only through reviving a natural functioning coastal lagoon system can a sustainable and resilient habitat for these endangered species be maintained at Sharp Park in the face of future climate change.”

Humans have altered Mediterranean landscapes and ecosystems for more than 8000 years, and despite human influences the region is considered a biodiversity hotspots. In the last few decades fire suppression policies have modified the ecosystems’ functioning, but prescribed burning has been considered a management tool to prevent extensive wildfires and restore the dynamics of fire-maintained ecosystems. Anna Sanz-Aquilar and colleagues (2011) assessed the impact of fire on survival rates, reproduction and movement of the Mediterranean Spur High Tortoise, Testudo graeca ibera, at the Cumbres de la Galera Biological Reserve, in the Sierra de la Carrasquilla, Spain. They found fire impacted survival of mostly of young individuals, with dramatic mortality of juveniles with the burned areas during the first and the second year after the fire. The reduction in vegetation cover after a fire could increase the visibility of young and vulnerable individuals to predators interfere with thermoregulatory behavior, or effect food availability. They found no differences in fecundity and movement patterns of tortoises between burned and unburned areas. Their, population models showed areas with fire frequencies of less than one fire every 20–30 years the tortoise populations seemed to cope with the effects of fires with little damage to the populations. But, when this fire frequency was surpassed, the probability of population extinctions exploded for all populations, except for those with the largest numbers of individuals. Thus, tortoise populations may be able to deal with naturally occurring fire frequencies, but the effects of more frequent fires may severely threaten the species.

Saturday, February 12, 2011

Cricket frogs of the genus Acris
are miniature, semi-aquatic hylids and despite the fact that they are
widespread and abundant at some locations their life histories are poorly
known. McCallum and colleagues used museum specimens and histology to determined
growth and seasonal size classes of the Northern Cricket Frog, Acris crepitans, from Georgia and
Florida) and Blanchard’s Cricket Frog, Acris
blanchardi, from Arkansas and Missouri. They found male and female
Blanchard’s Cricket Frogs metamorphose in the summer, and quickly reaches adult
size, females grow faster than males and some males are reproductively viable
by late summer. Most eggs develop in
spring and early summer with egg-laying in late May and June. The author’s size-class and histology data
suggests that few Acris survive more than one year, making them annual frogs.
Because these little anurans dedicate so much of their energy resources to
reproduction, environmental stress may make susceptible to pathogens such as chytrids,
which attack newly metamorphosed frogs. Thus, local extinctions may be
particularly common and account for the die-offs seen in the past half century.

The City of Opp’s Rattlesnake Rodeo Web site cautions, “The advice given is to avoid contact with rattlesnakes by remaining observant and not approaching the animals.” Good advice. Why then has the city offered a new bounty on rattlesnakes? Has it purchased sufficient liability insurance to cover the potential death and injury that could result? Did the city attorney warn against using public funds to encourage inexperienced people to seek out and capture deadly snakes? For the sake of the youngsters, I urge those responsible to change this ill-advised policy. If that’s not reason enough, think how damages from a single lawsuit could bankrupt the city!

While I’m talking change, many people feel it’s time to reconsider the Rodeo’s outdated, controversial, and exploitative “conservation” philosophy. Whether you appreciate rattlesnakes or not, what kind of message is it sending our children when they attend an event where a declining species of native wildlife is rounded up, often mistreated, and then slaughtered for no reason other than it’s a snake? Other towns that once had rattlesnake roundups have wisely evolved into differently-themed events. At the San Antonio Florida Rattlesnake Festival, education presentations feature snakes that are not abused or harassed, the crowd is entertained and children go home with a new appreciation and respect for wildlife. That event draws 30,000 visitors and raises thousands of dollars for local nonprofits.

This is a great time for a much-needed change to the Rattlesnake Rodeo. By being less exploitative to wildlife and more educational, it can be an even greater asset to our community. It doesn’t need to change its name, as a “roundup” would. It’s becoming less and less about the snakes, anyway. You don’t need 100 wild-caught snakes to have a beauty queen, car race, or concert. Why not keep a few snakes in captivity to put on display each year? Or to take it a step further, a friend who is a renowned authority on the eastern diamondback rattlesnake has suggested that to retain the “snake hunt” heritage, the Rodeo could establish a captive population, such as a secure snake pit, in which “hunters” could enter while spectators watch, and collect the snakes. A one acre pit landscaped with natural vegetation would still make this challenging. This would provide a new entertainment value (patrons of the event would actually get to see snakes being captured rather than just unloaded from boxes in the back of pickup trucks) and there would be no impact on wild populations of rattlesnakes, gopher tortoises, and other burrow inhabitants. The Miami Serpentarium has such an exhibit.

Full disclosure: I’m a wildlife biologist, active in Alabama’s conservation community for nearly 30 years. I appreciate and respect diamondbacks, and I co-exist with a few on my property in south Covington County. I understand why some might not share my enthusiasm, but if the Rodeo ever morphs into a rattlesnake festival that teaches the value of wildlife and instructs the public about nature, including how to avoid snakebite and what to do if it happens, many of my colleagues would gladly offer our services to help in making a festival atmosphere successful. I wish the Opp Rattlesnake Rodeo a long and successful future, but only if it changes with the times.

On account of the very high number of animal and plant species which are mostly only found here, Southeast Asia is a global biodiversity hotspot. Despite of its highly endangered terrestrial and freshwater ecosystems, Vietnam makes a significant contribution to this biological diversity. In a current publication the scientific team around Professor Madelaine Böhme, leader of the team on Terrestrial Palaeoclimatology of the Senckenberg Center for Human Evolution and Palaeoecology (HEP) at the University of Tübingen (Germany), demonstrates for the first time that North Vietnam was already a hotspot of biodiversity about 30 million years ago.

Kinship and evolutionary patternsThe group succeeded in recovering mammals, crocodiles, six species of turtles, around 20 fish species and 10 mussel species, snails and various plants from marine sediments as evidence of the early biodiversity. The publication presents the first scientific results of the German-Vietnamese research project carried out in 2008 and 2009 in North Vietnam under the leadership of Madelaine Böhme. Several of the fossil animals are completely new to science and are still awaiting a precise description. Even so, the yield in knowledge has already been considerable Professor Böhme sums up the objective of her research work: “Since many of the fossil species are closely related to today's plants and animals, the findings not only provide information on living conditions during the Cenozoic, but also help us to learn more about basic evolutionary patterns and the global mechanisms within the Earth system”.

The group investigated the Na Duong basin with the Rinh Chua fault in the province Lang Son, the Cao Bang basin North-West of it as well as the Hang Mon basin, not quite 300 kilometres South-Western of it, close to the Laotian frontier. All three basins lie along major dislocations which originated from powerful tectonic movements during the Eocene (c. 56–34 million years ago).

A map of primeval landscape Though the composition of the species spectrum differs within the single basins, the fossil record shows a remarkable variety of species. “These differences are very interesting and instructive for science", says Madelaine Böhme, and explains that if one is familiar with the single species, their way of life and needs, the fossils themselves tell much about their former way of life and the primeval environment. Together with geological observations, these information provide a sort of map. The results of the investigations thus sketch the primeval landscape of North Vietnam with the organisms and climatic conditions that once occurred there.

Because little is known yet about the fossil ecosystem of Vietnam, a great deal was also new to the scientists; that is why even the research team was surprised by the finds of 50 turtle shells within only ten days. They represent at least six genera. In the depositions which are millions of years old they also found tree-like ferns, fragments of tree trunks with up to five metres of length, fossil resins, different leaves and plant seeds. Beside parts of crocodiles and the remains of mammals belonging to a mouse deer and a rhinoceros the fossil report also mentions other vertebrates like small and medium-sized fish, barbel and one as yet undescribed teleost as well as catfish. Among the finds of molluscs there was an astonishing variety of completely different freshwater mussels and snails. Above all, the composition of fish and mussel fauna points to a habitat with shallow, oxygen-rich freshwater environments. These observations are supported by several aquatic plants, found in their live positions, which normally occur in tranquil waters, Madelaine Böhme assumes that the large mussel population provided clear water through its filtering activity and hence created ideal conditions for light-dependent plants.

Except for two additional representatives of the animal group, the finds of molluscs from the Rinh Chua formation do not differ from the mollusc deposits in the Na Duong basin. However the fish fauna differs significantly: the sediments contained several species of completely different carp-fish and also one catfish. In particular the deposits of fishes suggest that once a deeper freshwater ecosystem existed here.

In the approximately 70 square kilometres large Cao Bang basin both the geological results and the fossil finds indicate a primeval landscape with rivers, lakes and ponds. The fossil record for this region does not mention any mammals. Instead, there is evidence for animals which lived either in or at the edge of the water, including the remains of a gavial crocodile. Remarkable among the species-rich fish deposits is the fossil find of a giant barbel, which according to estimates, must have been up to two metres long. “This impressive fish find, by far the largest, must be classified not only as a new species but also as a new genus”, Madelaine Böhme declares. The fish fauna in the Cao Bang basin was not only impressive, but above all more numerous than in the Na Duong basin. In only 100 gram of sediment, remains of more than 100 fish were discovered. Like the molluscs, the fish species here differed overall from those in the Na Duong basin.

A new clue and further pending questionsThe diverse mussel fauna of the Na Duong and Cao Bang basins are still full of mysteries. The palaeontologists nevertheless consider it possible that on further investigation, the fossils recovered may not only turn out to be the oldest representatives of this animal group but also add a new clue to the discussions on the age of the basins.

The Hang Mon basin, at an altitude of 920 metres, presents neither fish nor aquatic mussels, with molluscs only represented by three different types of terrestrial snails, so that it is currently difficult to outline a habitat. Despite this, the absence of fish and aquatic mussels and the current evidence for primitive ungulates, as well as the evidence of mammals already cited in the literature, indicates a predominantly terrestrial habitat, perhaps traversed by rivers.

The comparison of the current fauna and flora of North Vietnam with that of the Cenozoic still raises a number of questions. One of the key regions for searching for traces of original conditions, such as the occurrence and extent of former and current freshwater organisms, is the Red River. Nowadays it flows through North Vietnam and ultimately into the Gulf of Tonkin, but it was already the main drainage system for Southeast Asia during the Palaeocene (65-23 million years ago) until the Neocene (23 -c. 5 million years ago). Whereas the Hang Mon basin formed a part of the drainage system of the Red River, there are indications that the basins along the Cao Bang-Tien Yen Fault were supplied in a different way. The geological and the fossil finds raise the question for Madelaine Böhme as to whether another large river might not have existed during the Cenozoic. This, as well as studies on climate and further geological and paleontological analysis, will form part of further research work on the past habitat and ecosystem of North Vietnam.

Oustalet's Chameleon,Furcifer oustaleti, a species endemic to Madagascar is
now known to be the second chamaeleonid to be introduced into the state of Florida. The
Veiled Chameleon, Chamaeleo calyptratus
, is the other species established in Florida. Furcifer oustaleti is one of the largest species
of chameleons, reaching 0.685 m. However, another Madagascar endemic, Calumma parsoniimay be the same size or larger. Another
introduced population of F. oustaleti may is suspected to exist in the vicinity of Nairobi, Kenya. The Florida population was started by
an animal dealer in Dade County, Florida sometime prior to December of 2000.
The extant population inhabits an avocado grove, contains both sexes, as well
as gravid females, and has been able to survive the cold snap of 2010. The
article is available on line from the Center of North American
Herpetology.

Thursday, February 10, 2011

Big bodied animals are often fossilized without their skulls
because the skull bones are frequently crushed and lost in time. The long standing confusion over what the Apatosaurus skull
actually looked-liked is a classic example. Hussam Zaher and colleagues have
now described Tapuiasaurus macedoi a
sauropod dinosaur and a member of the titanosaur clade. The description is
based upon an almost complete skeleton, including a well preserved skull
estimated to be 125-112 MYA. The skull resembles those of other titanosaurs
such asRapetosaurusfrom Madagascar andNemegtosaurusfrom Mongolia, because it has an
elongated snout, a nasal opening at the level of the eyes, and narrow crowns on
its teeth. However, Tapuiasauruspredated
these dinosaurs by at least 30 million years, suggesting the skull shape of the
Late Cretaceous titanosaurs evolved much earlier than previously thought. The complete article can be found on-line.

Leatherbacks. They are the Olympians of the turtle world – swimming farther, diving deeper and venturing into colder waters than any other marine turtle species. But for all their toughness, they have still suffered a 90 percent drop in their population in the eastern Pacific Ocean over the last 20-plus years, largely at the hands of humanity.

Now, new data from a 5-year-long project tagging and tracking the turtles are providing insights into their behavior, explaining why they congregate for months in what appeared to be one of the most nutrient-poor regions in the oceans, the South Pacific Gyre, and also helping researchers predict their movements on the high seas.

This new view of the lives of leatherbacks could offer a way to keep the turtles out of harm's way and give their numbers a chance to rebound.

"By taking the data we've gathered on their movements and integrating it with data on the surrounding oceanographic conditions, we've been able to identify what kind of habitats the leatherbacks prefer. This information is helping us develop models to predict where they might go and when they might show up there," said Stanford biologist George Shillinger, lead author of a paper to be published in Marine Ecology Progress Series and available online.

Until now, researchers didn't know why the leatherbacks that nest at Playa Grande in Costa Rica headed for the gyre and lingered for months. Satellite surface data suggested that this area spanning the Pacific Ocean between South America and New Zealand, from the low to mid-latitudes, appeared to be a virtual desert in the ocean, largely devoid of nutrients.

However, the presence of substantial tuna and swordfish fisheries within the region suggested there must be ample forage of some sort available.

Because only limited data exist concerning the diversity, abundance and distribution of the leatherback's favorite prey – gelatinous zooplankton, such as jellyfish – within the South Pacific Gyre, no one knew whether the turtles had food down there or not.

Following the food supply

"Nobody is really out chasing jellyfish down," Shillinger said. "They are poorly studied organisms and there is very little data on them in the region of the gyre."

But the data that came back from the tagged turtles suggest there may be plenty of jellyfish on which to feast.

"We saw a distinct reduction in the swimming speed of the turtles as they entered the South Pacific Gyre," Shillinger said. "They were making more turns, diving more frequently and diving deeper. All those things suggest feeding behavior."

Another piece of evidence was the timing of the turtles' dives. Like many marine organisms, jellyfish appear to engage in daily vertical migrations, moving into shallower depths at night and returning to somewhat deeper depths during the day.

The turtles' dives mirrored those movements, with their nighttime dives averaging about 38 meters deep, while average daytime dives were around 65 meters.

"The deepest dives we had in the data set were in the daytime, including the longest one, which was over 900 meters," Shillinger said. "That dive was also one of the longest leatherback dives ever reported. It was about 84 minutes." The cause for these superlative dives remains a mystery, although seeking prey and avoiding predators are likely motivations.

"Understanding what sort of areas leatherbacks are likely to favor is a critical first step in protecting them in the open ocean," he said.

From 2004 to 2007, Shillinger and his colleagues tagged 46 female leatherbacks on the beach in Costa Rica with satellite tags that broadcast information on location, depth and water temperature for an average of 245 days, with one tag transmitting for 562 days. "Altogether, it added up to 13,038 days of turtle tracking," Shillinger said.

One of the biggest hazards leatherbacks face on the high seas is longline fishing, a widely used approach for capturing commercially valuable species such as tuna and swordfish. The turtles also face fishing pressure from gill nets and longlines as they swim through coastal waters on their way out to the open ocean.

The problem, Shillinger said, is that areas that attract commercially desirable species also tend to be attractive to leatherbacks and other non-targeted species, known as by-catch.

"We are really going to have to link our research on turtles with a better understanding of where and how fishing is being done, things like how many hooks and nets are in the water and for how long," he said. "We also need to know more about the by-catch – which non-targeted species are being caught and in what numbers."

Having all that data would help Shillinger and his colleagues pinpoint the areas where fishing activity is most likely to coincide with turtle activity and determine what mitigation measures would be most effective.

Temporary closure of certain areas – breeding zones, migration routes and rich foraging habitats – when turtles are most likely to be concentrated there is one possible measure.

"We are not talking about closing the whole ocean. When the turtles have moved through, they can go back to fishing, in a lot of cases," Shillinger said.

Modification of fishing techniques, such as deploying hooks at the depths that are least likely to be occupied by turtles, could also help.

Shillinger emphasized that the timing of the turtles' presence, or the exact locations they inhabit, may well vary somewhat from year to year as ocean conditions vary, so mitigation measures will have to adapt to changing conditions.

'No one is out to kill turtles'

"No one is out to kill turtles," Shillinger said. "We are looking for solutions that are less adversarial with fishermen and more productive for turtle conservation."

The information collected from turtles in the South Pacific Gyre is already helping Shillinger and his colleagues refine their modeling of the turtles' movements.

Overall, Shillinger said, the leatherbacks showed an affinity for areas with cooler sea surface temperatures and stronger upwellings of deep, cool, nutrient-rich water, which drives in an increased abundance of life, including prey.

Another striking piece of data involved some synchronized swimming on the part of the turtles, Shillinger said. When the turtles hit about 35 to 37 degrees latitude south of the equator, they would stop swimming south and fan out along a belt to the east and west.

"They would be strung out hundreds of miles apart along this boundary and then, in concert, swing northward, all at about the same time," Shillinger said. "They might be responding to some sort of cue that we're not aware of, we just don't know. At this point, it is a mystery."

Although the temperature of the sea surface water decreases closer to the south pole, the leatherbacks can readily tolerate the colder water, so the researchers speculate that changes in the distribution of gelatinous zooplankton may have influenced the turtles not to go farther south. Or the turtles might just prefer to avoid the cooler waters, as it takes less energy to stay warm. The southern thermal bound occurred where the sea surface water temperature was about 14 to 15 degrees Celsius (57 to 59 degrees Fahrenheit).

"This information will help us refine our predictions regarding what sort of conditions attract leatherbacks, which is a challenge in the continually changing, highly dynamic conditions in the ocean," Shillinger said.

"Our hope is that these findings will further humanity's efforts to develop workable solutions for reducing our impacts and insuring the survival of this unique, enigmatic and critically endangered species."

Other Stanford-affiliated coauthors of the paper are Alan Swithenbank and Michael Castelton, both staff research technicians in the Block Lab at Hopkins Marine Station, and Barbara Block, professor of biology and a senior fellow at Stanford's Woods Institute for the Environment.

Shillinger is director of Marine Spatial Planning at the Center for Ocean Solutions, a partnership of Stanford University (through its Woods Institute for the Environment and Hopkins Marine Station), the Monterey Bay Aquarium and the Monterey Bay Aquarium Research Institute (MBARI). The Center for Ocean Solutions focuses on finding practical and enduring solutions to the greatest challenges facing the ocean.

At the time this research was conducted, Shillinger was a PhD candidate working at Stanford's Hopkins Marine Station in Barbara Block's laboratory.

Funding for this research was provided by the Tagging of Pacific Predators program of the Census of Marine Life, the Office of Naval Research, the UNESCO World Heritage Program, the Alfred P. Sloan Foundation, the Gordon and Betty Moore Foundation, the Packard Foundation, the Lenfest Ocean Program, the Cinco Hermanos Fund, Earthwatch Institute and NASA.

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